1. Field of Invention
Embodiments within the present disclosure relate, generally, to systems and methods for preventing improper lifting of tubular members through use of alarms responsive to the weight applied during a lifting operation, the position of a tubular member within a lifting device, or combinations thereof.
2. Background
When assembling a string of tubular members, such as a drill string or casing string, a lifting device, such as an overshot-type casing running tool, normally in conjunction with an elevator or similar gripping apparatus, is engaged with an individual tubular member, then used to move and/or rotate the tubular member to engage the tubular member with an adjacent portion of the tubular string. The lifting device is then disengaged from the tubular string, and the process is repeated. Similarly, when disassembling a string of tubular members, a single member of a tubular string may be engaged by a lifting device, rotated to disengage the tubular member from the string, then lifted and/or otherwise moved.
Conventionally, when engaging a lifting and/or running tool with a tubular member, one or more individuals on a rig floor and/or one or more other visual indicators are used to provide a signal to an operator when the tubular member reaches the correct position within the lifting device for engagement. If an operator continues to move the lifting device after this position has been reached, an improper engagement may result, and/or the lifting device may forcibly contact the tubular member, causing damage to the lifting device and/or the tubular member.
When performing assembly and/or disassembly operations, operator must repetitively perform a sequence of steps that include engaging tubular members with a lifting device, lifting and/or moving the tubular members, torquing the tubular members, disengaging the lifting device, and then repeating the process with subsequent tubular members. Due to the repetitive nature of such an undertaking, it is common for an operator to inadvertently skip one or more of these steps, or to lose awareness of the most recent action that was performed. Incomplete torquing of a tubular connection during disassembly may also create difficulty. As a result, it is possible to exceed the maximum lifting capacity of a lifting device by inadvertently attempting to lift multiple connected tubular members at one time. While some systems include visible signals that are provided when an improper lifting operation is undertaken, these signals are often overlooked, especially during situations in which the initial error resulted from operator inattention.
For example, during casing running procedures, a single common load is handled by two operators: a driller responsible for the rig, and the operator of the casing running tool. During casing running operations, the load must be transferred from an elevator or similar lifting apparatus having a limited capacity to the casing running tool. If any miscommunications occur between operators, or if any operations are performed improperly, loads exceeding the capacity of the equipment may be inadvertently applied.
A need therefore exists for systems and methods for preventing improper lifting of tubular members that instantly and effectively alerts operators, and other personnel at a work site, before damage may be incurred through an improper lifting operation.